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Posts tagged “Air Pollution”

Modeling the Impact of an Indoor Air Filter on Air Pollution Exposure Reduction and Associated Mortality in Urban Delhi Household

Liao J, Ye W, Pillarisetti A, Clasen TF. Modeling the Impact of an Indoor Air Filter on Air Pollution Exposure Reduction and Associated Mortality in Urban Delhi Household. Int. J. Environ. Res. Public Health 2019, 16(8), 1391; https://doi.org/10.3390/ijerph16081391    Supplementary Information

Indian annual ambient air quality standard is achievable by completely mitigating emissions from household sources

Chowdhury S, Dey S, Guttikunda S, Pillarisetti A, Smith KR, Di Girolamo L. Indian annual ambient air quality standard is achievable by completely mitigating emissions from household sources. Proceedings of the National Academy of Sciences Apr 2019, 201900888; DOI: 10.1073/pnas.1900888116. Supporting Information.

John Balmes: Don't Let a Killer Pollutant Loose

Professor John Balmes, close colleague and friend, and physician member of the California Air Resources Board:

PM 2.5 kills people. There has been little dispute that microscopic particulate matter in air pollution penetrates into the deepest parts of the lungs and contributes to the early deaths each year of thousands of people in the United States with heart and lung disease.

One recent study called PM 2.5 “the largest environmental risk factor worldwide,” responsible for many more deaths than alcohol use, physical inactivity or high sodium intake.

The Environmental Protection Agency’s own website says: “Numerous scientific studies have linked particle pollution exposure to a variety of problems, including: premature death in people with heart or lung disease, nonfatal heart attacks, irregular heartbeat, aggravated asthma, decreased lung function, increased respiratory symptoms.”

Which makes it deeply troubling that the very people at the helm of the Trump administration’s E.P.A. responsible for protecting public health and the environment are now pursuing a course that would make the air we breathe even more hazardous.

Understanding Air Pollution with Art: "The Air of the Anthropocene" and "Mutual Air"

Playground, India Institute of Technology Campus, Delhi, India - PM2.5 500 - 600 µg/m3

Artist Robin Price and Professor Francis Pope use experimental photography to “see” small particles as part of their “Air of the Anthropocene” project (h/t Zoe Chafe). The photos are stunning. From a Guardian piece highlighting many of the photos:

Using a custom-built digital light painter and wearable particulate sensor, I take long exposure photographs that paint the amount of PM2.5 particles in the air as particles of light. As the light painter’s sensor detects more pollution it draws correspondingly greater numbers of light particles into the photograph. The effect is as if the microscopic pollution has been enlarged and lit up, shedding light on the invisible particles.

Meanwhile, in the Bay Area, Artist Rosten Woo uses chimes to make air pollution audible:

Mutual Air is a network of roughly thirty specially designed bells that generate a soundscape reflecting and responding to the changing composition of our local and global atmosphere. By sonifying air-quality fluctuations, Woo hopes​ to engage the public in an experiential understanding of climate science and how aspects of our atmosphere, while a shared resource, reflect socioeconomic disparities.

His work was featured on PBS News Hour:


See also Smog Meringues and British Pathe - Air Pollution

Indian Election Analysis: Election manifestos feature air plan but little action on ground

A new report titled “Political Leaders Position and Action on Air Quality in India” released by Climate Trends also highlighted that members of parliament in 14 Indian cities, among the most polluted cities globally as per the WHO 2018 urban air quality database, have done little to get their cities to comply with safe air quality standards locally.

“The manifestos of both the national parties have proven that political parties cannot ignore and neglect air pollution related health emergency any more. This rhetoric is a good sign. But the bigger question is - if this electoral promise will translate into strong enough political will to push for hard action with accountability and show results,” said Anumita Roychowdhury, executive director, Centre for Science and Environment. Delhi’s air pollution levels recorded a fall in 2018 because of multiple strategies, she added.

Energy and Health in the 2019 BJP Manifesto

The BJP’s Manifesto was released in the last few days. A little hard to hunt down, initially, though a PDF is hosted at documentcloud.

In a section that is partly a list of achievements and partly a description of next steps:

We have evolved technologically better strategies and devices to map the level of pollution in cities and rivers and have taken effective steps to reduce the level of pollution in major cities, including the national capital. We will convert the National Clean Air Plan into a Mission and we will focus on 102 most polluted cities in the country. Through concerted action, we will reduce the level of pollution in each of the mission cities by at least 35% over the next five years.

Another part of he Manifesto is framed around 75 milestones for India’s 75th anniversary, including some focusing on health, energy, air pollution, and water & sanitation.

Under Infrastructure:

Ensure a pucca house to every family. Ensure the LPG gas cylinder connection to all poor rural households. Ensure 100% electrification of all households. Ensure a toilet in every household. Ensure access to safe and potable drinking water for all households. Bharat Mission to achieve ODF+ (Open Defecation Free) and ODF++ in cities and villages. Ensure ODF status for all villages and cities.

Under good governance:

Work towards substantially reducing the current levels of air pollution. Work towards completely eliminating crop residue burning to reduce air pollution.

New Yorker: The Hidden Air Pollution in Our Homes

Nice piece by Nicola Twilley, co-host of Gastropod:

“So there is a big question here,” Marina Vance pointed out. “If all these studies have found an association between outdoor air pollution and a decrease in life quality and life expectancy, but we’re not outside, how does that relationship still hold?”

One possibility is that the brief moments we spend outdoors have an outsized impact on our health. Another consideration is that outdoor pollutants can and do come inside. But one homechem researcher, Allen Goldstein, recently co-authored a paper that suggests a fascinating inversion. The dominant source of VOCs in Los Angeles is now emissions from consumer products, including toiletries and cleaning fluids. In other words, vehicle emissions have been controlled to such an extent that, even in the most car-clogged city in America, indoor air that has leaked outdoors may create more smog than transportation does.

It’s true — some surveys done in the last couple of decades show that people in North America spend, on average, 90% of their time indoors. It’s unlikely that our air pollution exposures — measured as ambient concentrations at central sites, far from where we live and spend time — capture what’s really going on.

One point of contention with this article — despite some nice historical thinking on the relationships between indoor and outdoor air, there was no mention of the very large exposures that continue in the developing world, where solid fuels like wood, grass, dung, and coal are used indoors. A substantial oversight.

Update: Nicola Twilley wrote on twitter that mention of the developing world didn’t make the final version.

Science vs Fringe Thinking: EPA Science Panel Considering Guidelines That Upend Basic Air Pollution Science

NPR, reporting on a recent EPA Meeting:

At a public meeting Thursday that ran nearly two hours long, multiple members of that committee, including Chair Tony Cox and Steven Packham of the Utah Division of Air Quality, said they do not agree that breathing air polluted with soot can lead to an early death.

“[Committee] members have varying opinions on the adequacy of the evidence supporting the EPA’s conclusion that there is a causal relationship between [particulate matter] exposure and mortality,” said Cox, reading from the committee’s draft recommendations before explaining that he is “actually appalled” at the lack of scientific evidence connecting particulate pollution to premature death.

From Nature:

A quarter of a century of research has shown that breathing in fine airborne particles emitted by cars, power plants and other sources shortens people’s lifespans. But that scientific consensus is now under attack from a top advisor to the US Environmental Protection Agency (EPA), just as the agency is rushing to revise the national air-quality standard for such pollution before the end of President Donald Trump’s first term. Scientists fear that the result could be weaker rules on air pollution that are bad for public health — and based on politics, not science.

The case has been made — repeatedly — that the health and economic benefits of the Clean Air Act and subsequent regulatory processes are clear. This is summarized succinctly in the figure below, which shows energy consumption, vehicle miles traveled, GDP, and total emissions of EPA criteria pollutants.

Figure from The Lancet Commission on Pollution and Health

Let’s put aside the economic argument and focus on the principles that undergird the Clean Air Act - protection of public health, with standards set to protect the most vulnerable. This critical prerogative is undermined by these (and other) recent efforts to roll back regulations that have clear and demonstrable health benefits. This is yet another example of the Trump administration’s abnegation of responsibility to the health and welfare of the US population.

For more information, see Gretchen T. Goldman and Francesca Dominici’s discussion in Science and their claim-by-claim evidence base. See also a nice summary of the issue at NRDC and a letter from Professor John Samet to the EPA that comprehensively outlines issues with changes to the evidence review process for the National Ambient Air Quality Standards.

Air Pollution in Asia and the Pacific: Science-based solutions

Hong Y-C, Hicks K, Malley C, Kuylenstierna J, Emberson L, Balakrishnan K, Pillarisetti A, Sunwoo Y, et al. (2018). Air Pollution in Asia and the Pacific: Science-based solutions. United Nations Environment Programme (UNEP) , Bangkok, Thailand. pure.iiasa.ac.at/15561. peer reviewed.

Tracking ambient PM2.5 build-up in Delhi national capital region during the dry season over 15 years using a high-resolution (1 km) satellite aerosol dataset

Chowdhury S, Dey S, Di Girolamo L, Smith KR, Pillarisetti A, Lyapustin A. Tracking ambient PM2.5 build-up in Delhi national capital region during the dry season over 15 years using a high-resolution (1 km) satellite aerosol dataset. Atmospheric Environment 204: 142-150. doi.org/10.1016/j.atmosenv.2019.02.029

Emissions from village cookstoves in Haryana, India and their potential impacts on air quality

Fleming LT, Weltman R, Yadav A, Edwards RD, Arora NK, Pillarisetti A, Meinardi S, Smith KR, Blake DR, Nizkorodov SA. 2018. Emissions from village cookstoves in Haryana, India and their potential impacts on air quality, Atmos. Chem. And Phys. 18: 15169-15182 doi.org/10.5194/acp-2018-487

The gains in life expectancy by ambient PM2.5 pollution reductions in localities in Nigeria

Etchie TO, Etchie AT, Adewuyi GO, Pillarisetti A, Sivanesan S, Krishnamurthi K, Arora NK. 2018. The gains in life expectancy by ambient PM2.5 pollution reductions in localities in Nigeria. Environmental Pollution 236: 146-157. doi.org/10.1016/j.envpol.2018.01.034

Small, Smart, Fast, and Cheap: Microchip-Based Sensors to Estimate Air Pollution Exposures in Rural Households

Pillarisetti A*, Allen T, Ruiz-Mercado I, Edwards R, Chowdhury Z, Garland C, et al. 2017. Small, Smart, Fast, and Cheap: Microchip-Based Sensors to Estimate Air Pollution Exposures in Rural Households. Sensors. doi.org/10.3390/s17081879

The impact of household cooking and heating with solid fuels on ambient PM2.5 in peri-urban Beijing

Liao J, Zimmerman A, Chafe ZA, Pillarisetti A, Yu T, Shan M, Yang X, Li H, Liu G, Smith KR. 2017. The impact of household cooking and heating with solid fuels on ambient PM2.5 in peri-urban Beijing. Atmospheric Environment. doi.org/10.1016/j.atmosenv.2017.05.053

Air pollution-related health and climate benefits of clean cookstove programs in Mozambique

Anenberg SC, Henze DK, Lacey F, Irfan A, Kinney P, Kleiman G, Pillarisetti A. 2016. Air pollution-related health and climate benefits of clean cookstove programs in Mozambique. Environmental Research Letters. doi: 10.1088/1748-9326/aa5557

The Return of London's Fog

London’s fogs may be about to make a comeback. Christine Corton, in the NYT:

In January, researchers at King’s College London announced that pollution levels on Oxford Street, in central London, had exceeded limits set for the entire year in just the first four days of 2015. Similarly alarming numbers have been recorded for other streets in the city — and yet the mayor, Boris Johnson, has delayed implementation of stricter air-quality measures until 2020.

What’s happening in London is being played out in cities worldwide, as efforts to curtail the onslaught of air pollution are stymied by short-term vested interests, with potentially disastrous results.

I just experienced a particular, particulate version of this hell first-hand in Delhi. For the last few days of my trip, a dense, thick haze - clearly not an innocuous fog - permeated the city and surrounding environs. On one trip back to our flat, all of my fellow taxi passengers complained of burning eyes and sore throats.

The closest PM monitor during that drive back — actually quite far from us — read over 250 µg/m3. That’s around 10x higher than a ‘bad’ day in the US. Moreover, we guessed that the levels we were experiencing were closer to 350 µg/m3. As a point of reference, the maximum mean hourly PM2.5 concentration in London since 2008 was approximately 30 µg/m3.

Corton points to a behavioral component to the historic London Fog episodes — a parallel I find particularly interesting:

There was a cultural component, too. The British were wedded to their open fires. Closed stoves, popular throughout much of Europe, especially in Germany, were shunned by Londoners. During World War I, Britons were exhorted, in the words of the famous song, to “keep the home fires burning.” Politicians were simply not willing to risk unpopularity by forcing Londoners to stop using coal and go over to gas or electric heating instead. In Britain today, in an echo of these earlier concerns, the government is cutting subsidies for onshore wind and solar farms, anxious not to offend voters in rural areas where such facilities would be built.

It took a disaster to force London to change direction. In 1952, a “great killer fog” lasted five days and killed an estimated 4,000 people. In a Britain trying to turn a corner after the death and destruction of the Blitz, this was unacceptable. A Clean Air Act was passed in 1956, forcing Londoners to burn smokeless fuel or switch to gas or electricity, power sources that had become much cheaper as these industries expanded.

Let’s hope that policy levers and momentum — not a disaster — can help transition away from solid fuels in India and beyond.

Conditional cash transfers for energy poverty... and murder reduction

Conditional cash transfers — paying people to change behavior, usually to spur positive ‘social’ outcomes — continue to be in the news. Much of the focus is on their use as poverty reduction tools (Bolsa Familia in Brazil, JSY in India) through encouraging behaviors like antenatal care visits and sending children to school.

Two recent article — one in the NYT, one in Mother Jones — highlighted the use of CCTs and other targeted cash transfer tools for dramatically different outcomes.

In the NYT, poverty and energy issues were at the fore:

The Indian government subsidizes households’ purchases of cooking gas; these subsidies amounted to about $8 billion last year. Until recently, subsidies were provided by selling cylinders to beneficiaries at below-market prices. Now, prices have been deregulated, and the subsidy is delivered by depositing cash directly into beneficiaries’ bank accounts, which are linked to cellphones, so that only eligible beneficiaries — not “ghost” intermediaries — receive transfers.

Under the previous arrangement, the large gap between subsidized and unsubsidized prices created a thriving black market, where distributors diverted subsidized gas away from households to businesses for a premium. In new research with Prabhat Barnwal, an economist at Columbia University, we find that cash transfers reduced these “leakages,” resulting in estimated fiscal savings of about $2 billion.

There’s even more “smart” targeting coming soon. My advisor and colleagues in India have been working to “[describe] how the LPG subsidy could be even more completely targeted to the poor without any actual ‘taking away’ of the subsidy from the rich and middle class, which would likely trigger heavy political push back. As a result, several hundred million additional poor Indians could have affordable access in the next decade without increasing subsidy costs to the government (indeed probably reducing them) or LPG imports — both not likely to be popular.”

In Mother Jones, CCTs were being used to reduce murders:

Richmond hired consultants to come up with ideas, and in turn, the consultants approached [Devone] Boggan. It was obvious that heavy-handed tactics like police sweeps weren’t the solution. More than anything, Boggan, who’d been working to keep teen offenders out of prison, was struck by the pettiness of it all. The things that could get someone shot in Richmond were as trivial as stepping out to buy a bag of chips at the wrong time or in the wrong place. Boggan wondered: What if we identified the most likely perpetrators and paid them to stay out of trouble?

It seems to be working.

It was a crazy idea. But since ONS was established, the city’s murder rate has plunged steadily. In 2013, it dropped to 15 homicides per 100,000 residents—a 33 year low. In 2014, it dropped again. Boggan and his staff maintained that their program was responsible for a lot of that drop-off by keeping the highest-risk young men alive—and out of prison. Now they have a study to back them up.

On Monday, researchers from the National Council on Crime and Delinquency, a non-profit, published a process evaluation of ONS, studying its impact seven years in. The conclusion was positive: “While a number of factors including policy changes, policing efforts, an improving economic climate, and an overall decline in crime may have helped to facilitate this shift, many individuals interviewed for this evaluation cite the work of the ONS, which began in late 2007, as a strong contributing factor in a collaborative effort to decrease violence in Richmond.”

Ye Olde Smog Meringue

image from coclimate.com

Nicola Twilley, writing at ediblegeography.com:

After running around New York City in order to source our precursor ingredients (a huge thanks to Kent Kirshenbaum, chemistry professor at NYU and co-founder of the Experimental Cuising Collective), we spent Thursday afternoon and evening in the kitchens of Baz Bagel (excellent bagels, amazing ramp cream cheese, and truly lovely people) assembling the cart, mixing different chemical precursors, and then “baking” them under UV light to form a London peasouper, a 1950s Los Angeles photochemical smog, and a present-day air-quality event in Atlanta.

We chose these three places and times to showcase three of the classic “types” that atmospheric scientists use to characterize smogs: 1950s London was a sulfur- and particulate-heavy fog, whereas 1950s Los Angeles was a photochemical smog created by the reactions between sunlight, NOx, and partially combusted hydrocarbons. Present-day Beijing often experiences London-style atmospheric conditions, whereas Mexico City’s smog is in the Angeleno style.

Meanwhile, at its worst, Atlanta’s atmosphere is similar in composition to that of Los Angeles, but with the addition of biogenic emissions. An estimated ten percent of emissions in Atlanta are from a class of chemicals known as terpenes, from organic sources such as pine trees and decaying green matter. We had also hoped to create a Central Valley smog as well, but time got the better of us.

Each city’s different precursor emissions and weather conditions produce a different kind of smog, with distinct chemical characteristics—and a unique flavour.

Field Notes - Measuring Village Air Pollution in Bajada Pahari

Twenty minutes from INCLEN’s SOMAARTH field headquarters lays Bajada Pahari1, a sleepy, picturesque village of ~120 households. The road to Bajada Pahari twists through bustling little villages, becoming more and more narrow until what remains is suited more for bullock carts, tractors, goats, and shepherds than personal vehicles. As the settlements dwindle, large open croplands — of tall sugarcane, bright yellow mustard, and various green sabjiyom2 — dominate the field of view. Enormous metal structures for high voltage powerlines stand erect yet untethered: no cables connect them. Below, and all around, the landscape is dotted with small, oblong discs of gobara3 used for fertilizer and as fuel.

Bajada Pahari is trapezoidal in shape, buttressed to its north by a small hill, upon which sits an old, abandoned watchtower4 and a small informal shrine to Shiva marked by narrow, red flags. Immediately behind the ridge, a green pool sparkles in the hazy winter daylight. Stray dogs roam a nearby shallow dig - perhaps an old quarry. Looking away from the village, pasturelands extend for as far as the eye can see. Barely visible brick kilns spew grayish black emissions. From the hilltop, the only audible sounds are chirping birds and rustling leaves, punctuated occasionally by a wailing child, a barking dog, a puttering engine.

We arrived in Bajada Pahari mid-morning and went first to the home of the Sarpanch, the head village elder5. At his residence, on the edge of town, a large gate opens first into a foyer full of mechanical farm tools — a tractor, a manual chopper — and a few simple cots and then leads into an outdoor space with trees, cows, chairs, and chulas. The Sarpanch arrived shortly thereafter, on a motorcycle bearing his title. After initial pleasantries and introductions, we discussed the village, which won an award for progress on sanitation and cleanliness, and our air pollution project.

Village air pollution is a hard concept to grok. For most, the pervasive images conjured by the word ‘rural’ are clean and pure, especially compared to places like Delhi, Mumbai, and Beijing. The sources of air pollutant emissions are no doubt different — quaint cookstoves, open fires, brick kilns, and small village industries look innocuous when compared to massive smokestacks and endless diesel vehicles visible in large Indian cities6. Tens to hundreds of these little village sources, simultaneously used over a small geography, probably adversely impacts air quality. Think of each one as a small contributor to a larger village smokestack.

The sarpanch is (unsurprisingly) thoughtful, measured, and interested. Mayur explains what we’d like to do, and why, succinctly and in simple language - a difficult feat he has perfected in his years with INCLEN. We talk about why we’re interested in understanding air pollution in a rural village (unmeasured, significant, and likely related to simple combustion of wood and dung) and why we think it’s important (trying to convince government to monitor and regulate the entire airshed, not just in urban areas). We show him some of our toys — including a miniature quadcopter, similar to the larger one we’ll use to measure some meteorological parameters and PM2.5. He laughs at the copter and approves of our plans. He decides we should discuss further with others on the village council.

We walk down the street, past a few cows lounging next to an abandoned biogas plant. At the intersection of two of the town’s biggest roads, a group of men and empty plastic chairs await us. Our discussion with them is similar to the previous one with the sarpanch. A few sarcastically questioned if we are asking them to stop cooking entirely. Others suggested their households, as proxies for the village, would be enthusiastic to move to LPG if the hassle of acquiring fuel wasn’t so great. They noted that there were no home deliveries and that it was difficult to coordinate pickup and dropoff of the cumbersome cylinders. One man, in particular, railed against the notion that food cooked on LPG was any different than that cooked over an open fire; he opined that it wasn’t the fuel that made the food, but the cook. His example was of village boys, who move to a city and eat food cooked on LPG by a stranger; they blame the poor taste on the fuel. He blamed the cook — or, more accurately, the fact that this food wasn’t the food they grew up eating, that they were accustomed to. A pretty neat (and new) insight. Not atypically, we spoke with only men about tasks they weren’t directly involved with.

We learned a little about electricity in the village, as well. It is reliable and consistent — rare for these areas. It arrived first in 1978. Many households have multiple electric appliances, including a washing machine, metal rods used to heat water, fans, and small electric stoves known as ‘heaters’. Our final task in the village involved locating a site to place an ambient air pollution and meteorological monitor, along with associated solar panels. We found a nice rooftop location, in the center of town, adjacent to a beautiful, decaying old farmhouse.


1 Alternate spellings include Bajda Pahadi, Bajda Pahari, Bajada Pahadi, and various other permutations. Depending on the spelling, the town’s name takes different meanings. My favorite is “lazy hill,” which sums it up succinctly. Bajada also has a Spanish meaning, which is curiously on point: “a broad alluvial slope extending from the base of a mountain range into a basin” or, more simply, “descent, slope.”

2 Vegetables

3 Dried bovine dung

4 The history of the tower is a little ambiguous; some of the village boys said it was an old British outpost, while others claimed it is a much older Mughal structure.

5 The sarpanch serves as a link between the local and regional governments and the community. There’s some push to pass along certain judicial and legislation-related powers to Sarpanches.

6 The situation is complicated by a national emphasis on cities as thriving centers of vitality, modernity, and growth. The concerns of rural villages don’t align with those of the metropolis - as such, their ranking in the national conscious and in the media is low. This despite ~80% of the population living in rural areas.

British Path�'s films on smog and air pollution

From Variety:

British Path�, the U.K. newsreel archive company, has uploaded its entire 100-year collection of 85,000 historic films in high resolution to YouTube.

The collection, which spans 1896 to 1976, comprises some 3,500 hours of historical footage of major events, notable figures, fashion, travel, sports and culture. It includes extensive film from both World War I and World War II.

Naturally, I looked for some videos about smog, air pollution, and the environment. The Archive doesn’t disappoint. There are pieces called “The Smog Menace”, “Smog Detector”, and a documentary called “Guilty Chimneys” (part 1 + 2, part 3).

There’s a lot of fascinating stuff in the archive beyond smog and air pollution. Pretty cool.